The present invention relates to an improved adhesive tape having an edge coating. More specifically, the present invention relates to an edge coating for masking tape and other masking materials that improves the masking ability of those materials.
Adhesive tapes for masking are typically comprised of a paper substrate having an adhesive layer applied to a bottom surface thereof. In addition, some masking tapes have an upper, liquid-resistant, or liquid-proof layer applied to an upper surface of the substrate. A persistent problem with masking tapes of this type is that the tape is typically only partially successful in defining a clean masking edge or boundary between masked and unmasked surfaces. For example, when an unmasked surface is painted, it is common for paint to work its way into gaps between the adhesive layer of the tape and the surface to which the tape is applied. In addition, the paper substrate has a tendency to absorb or wick moisture from the paint through the unprotected edge of the tape substrate. This absorption causes swelling in the tape that degrades the ability of the tape to form a tight seal with the surface to which it is applied.
Yet another problem associated with masking tape and other, similar masking products is that paint that overlies the edge of the tape will cure in place and make it difficult to remove the tape from beneath the edge of the layer of cured paint. In these circumstances, tape can tear or worse, remove portions of the cured paint, thereby necessitating touch up of the painted surface.
Accordingly, it is an objective of the present invention to provide an edge coating that eliminates or at least minimizes the movement of paint or other liquids past a boundary defined by a masking edge of an adhesive tape or other masking product. It is another object of the present invention to provide an absorbent edge coating that will prevent or at least minimize liquids from being wicked into the substrate of an adhesive tape or other masking product. A final objective of the present invention is to provide an edge coating for an adhesive tape or other masking product that retards the curing of paints or other coatings applied to a surface at a boundary between an unmasked area and a masked area of a surface, thereby facilitating the clean release of the adhesive tape or masking product from the surface to which it is applied.
These and other objectives and advantages of the invention will appear more fully from the following description, made in conjunction with the accompanying drawings wherein like reference characters refer to the same or similar parts throughout the several views.
The objects of the present invention are realized in a masking tape having a substrate with a top surface, a bottom surface, a first edge, and a second edge. The bottom surface of the substrate has an adhesive layer applied thereto and at least one of the edges of the substrate, also referred to as a masking edge, has an absorbent edge coating that substantially prevents liquids addressed thereto from being absorbed into the substrate of the tape and from passing between the bottom surface of the tape and a surface to which the tape has been applied. The edge coating is preferably a super absorbent polymer and has an absorbency that is greater than that of the substrate of the tape. In this manner, the edge coating reduces or substantially prevents the absorption of liquids into the substrate and also prevents the movement of the liquids beneath the tape. The super absorbent polymers of the edge coating also absorb and retain excess liquids addressed to the coated edge in such a manner as to retard the curing of the liquids. By retarding the curing of the liquids at the edge of the substrate, the absorbent edge coating facilitates the clean release of the tape from the surface to which it has been applied and from the remaining liquid applied to the surface.
Preferably, the substrate of the tape will be fashioned of a paper product such as a paper crepe ribbon though it is envisioned that the tape may also be fashioned from polyethylene, polyester, or other synthetic materials as well. To further prevent the absorption of the liquids into the substrate of the tape, a liquid resistant layer may be applied to the top surface of the substrate of the tape. Alternatively, a liquid-proof layer applied to the top surface of the substrate of the tape.
The present invention may also be characterized as an improved masking tape for defining a boundary between a masked area of a surface and an unmasked area of the surface. Such a masking tape comprises an elongate substrate having a top surface, a bottom surface, and at least one masking edge. An adhesive layer is applied to the bottom surface of the substrate for adhering the masking tape to the surface. An absorbent edge layer is also applied to at least one masking edge of the substrate to at least substantially prevent or minimize liquids applied to the unmasked area of the surface from moving past the boundary on the surface that is defined by the at least one edge of the substrate to which the absorbent edge layer is applied. Preferably the absorbent edge layer will be a super absorbent polymer capable of absorbing water, oil based paint, latex paint, stains, glazes, dyes, cleaning compounds, strippers, and solvents. Furthermore, the absorbent edge layer applied to the at least one masking edge is able to absorb and retain liquids applied thereto in such a manner as to retard the curing of the liquid located at the boundary.
The present invention may comprise a roll of tape or a masking article that has had an absorbent edge coating applied during the original manufacturing process, or may comprise an absorbent edge coating that is applied to a roll of tape or to a masking article immediately prior to its use. A method of manufacturing an adhesive tape that includes an absorbent edge coating begins with the step of providing a substrate that has a top surface and a bottom surface. An adhesive layer is applied to the bottom surface of the substrate. The substrate is subsequently rolled onto a cylindrical core and cut into discrete rolls. The absorbent material that makes up the edge coating is applied to at least one cut edge of the discrete rolls such that the absorbent material is adhered to the edge of the substrate exposed on the cut edge of the roll by the adhesive layer applied to the bottom surface of the substrate.
A roll of tape constructed and arranged according to the present invention and having a top, a bottom, and a masking edge with a predetermined shape and an absorbent layer applied thereto is employed in masking off a first area of a surface from a second area of the surface by applying the tape to the surface such that the masking edge of the tape is coincident with the boundary between the first and second areas of the surface. An adhesive layer applied to the bottom surface of the tape adheres the tape to the surface to which it is applied. The absorbent layer on the masking edge of the tape is preferably a super absorbent polymer.
The present invention may also be embodied in various masking materials used to define a boundary between a masked area of a surface and an unmasked area of the surface. Such masking materials comprise a substrate having a top surface, a bottom surface, at least one edge, an adhesive layer applied to at least a portion of the bottom surface of the substrate for adhering the masking material to the surface, and an absorbent edge layer that is applied to the at least one edge of the substrate. The absorbent edge layer at least substantially prevents liquids applied to the unmasked area of the surface from moving past the boundary on the surface that is defined by the at least one edge of the substrate to which the absorbent edge layer is applied. Again, its is preferred that the absorbent edge layer be made of a super absorbent polymer. These super absorbent polymers absorb and retain liquids applied to the surface in such a manner as to retard the curing of the liquid absorbed, thereby facilitating the clean release of the edge of the tape from the surface to which it has been applied and from the remaining liquid applied to the surface.
The absorbent edge coating may also be employed with a roll of tape that is to be applied for masking purposes with a bi-directional tape dispensing device that is capable of applying tape around and into the corners of a first surface wherein the first surface may be adjacent to a second surface. When so employed, such a tape dispensing device may comprise a frame having an alignment member extending from the frame and a hub rotatably attached to the frame and adapted for receiving a roll of tape. As will be appreciated the roll of tape will comprise an elongate substrate having a top surface, a bottom surface, and at least one masking edge. An adhesive layer is applied to the bottom surface of the substrate for adhering the tape to one of the first and second surfaces, and an absorbent edge layer applied to the at least one masking edge of the substrate to at least substantially prevent liquids applied to one of the first and second surfaces from moving past a boundary on the first or second. The boundary is defined by the at least one masking edge of the substrate to which the absorbent edge layer is applied. The roll of tape is received by the hub such that the at least one masking edge of the tape is aligned with an outer edge of the alignment member. Furthermore, the roll of tape may be pressed onto the hub with the at least one masking edge of the roll of tape being oriented on the bi-directional tape dispenser independent of a width of the roll of tape and with no dependency on an inner edge of the roll of tape.